Bridge pre-back pressure device

Abstract

The utility model provides a bridge pre-counter-pressure device. The bridge pre-counter-pressure device comprises a fixed base, a counter-force frame, a connecting assembly and a jacking assembly. The fixed base is arranged below the bridge bracket; the counter-force frame is arranged above the bridge bracket; the connecting assembly comprises a vertically-arranged connecting rod, the upper end of the connecting rod is connected with the counter-force frame, and the lower end of the connecting rod is connected with the fixed base. The jacking assembly is provided with a jacking driving piece, the top end of the jacking driving piece is connected to the counter-force frame, and the bottom end of the jacking driving piece abuts against the top of the bridge bracket. According to the bridge pre-counter-pressure device, the fixed base is arranged below the bridge bracket, the counter-force frame is fixed to the fixed base through the connecting rod, the jacking driving part is arranged between the bridge bracket and the counter-force frame, and when the jacking driving part jacks the counter-force frame upwards, the counter-force frame is fixed through the connecting rod, so that the jacking driving part exerts force in the reverse direction; the bridge bracket is pushed to move downwards, and the compression capacity of the bridge bracket can be detected.

Description

Technical Field

[0001] The utility model belongs to the technical field of bridge construction, and in particular relates to a bridge pre-back pressure device. Background Art

[0002] During the construction of bridge piers, especially when the pier column where the pier top block No. 0 is located is high, it is necessary to install a bracket on the pier top as the construction support system for the pier top block No. 0. After the bracket is installed, in order to verify the structural safety of the cast-in-place bridge bracket, eliminate the inelastic deformation of the structure, and measure the elastic deformation of the bridge bracket, it is necessary to pre-reverse pressurize the bracket.

[0003] At present, the pre-counter pressure of bridge brackets adopts the method of piling heavy objects on the bridge. The heavy objects need to be transported to the top of the bridge bracket for use. Due to the high density of heavy objects and the difficulty in moving them, the operation of transporting them to high altitudes is highly dangerous. In addition, moving multiple heavy objects leads to high transportation costs and great difficulty in transportation. Utility Model Content

[0004] The embodiment of the utility model provides a bridge pre-back pressure device, which aims to solve the technical problems in the prior art that heavy objects exerting pressure on bridge brackets are difficult to move and have certain dangers during transportation.

[0005] In order to achieve the above-mentioned purpose, the technical solution adopted by the utility model is: to provide a bridge pre-back pressure device, comprising:

[0006] The fixed base is arranged below the bridge bracket and is fixed relatively to the ground;

[0007] The reaction frame is located above the bridge bracket;

[0008] A connecting assembly, comprising a vertically arranged connecting rod, the upper end of which is connected to the reaction frame, and the lower end of which is connected to the fixed base; and

[0009] The jacking assembly comprises a jacking driving member, the top end of which is connected to the reaction frame, and the bottom end of which is abutted against the top of the bridge bracket.

[0010] In a possible implementation, the connecting assembly also includes a limit plate, which is arranged above the reaction frame along the width direction of the reaction frame, and the bottom end of the limit plate abuts against the upper surface of the reaction frame. Two connecting rods are provided, and the two connecting rods are respectively connected to the two ends of the limit plate.

[0011] In a possible implementation, the long axis of the reaction frame is perpendicular to the length direction of the bridge bracket; the connecting components are provided in plurality, and the plurality of connecting components are arranged at intervals along the long axis of the reaction frame; the two connecting rods in the same connecting component are respectively located on opposite sides of the reaction frame, and the long axis of the limit plate is perpendicular to the long axis of the reaction frame.

[0012] In a possible implementation, the jacking assembly further includes a fixing seat, the bottom end of the jacking drive member is connected to the fixing seat, and the fixing seat abuts against an upper surface of the bridge bracket.

[0013] In a possible implementation, the fixing seat is provided with a guide rod extending upward, the reaction frame is provided with a guide channel corresponding to the guide rod, and the guide rod is slidably engaged with the guide channel.

[0014] In a possible implementation, the connecting assembly also includes an upper fastener, and a connecting hole that passes through the limit plate corresponding to the connecting rod is provided up and down. The top end of the connecting rod passes through the connecting hole and is screwed to the upper fastener, and the upper fastener abuts against the top end of the limit plate to limit the rise of the limit plate.

[0015] In one possible implementation, a positioning rod is provided on the top of the fixed base, the positioning rod is a screw rod, an external thread is provided on the bottom of the connecting rod, and the rotation directions of the positioning rod and the connecting rod are opposite; the connecting assembly also includes a connecting sleeve, and the two ends of the connecting sleeve are respectively screwed to the positioning rod and the connecting rod.

[0016] In a possible implementation, the fixed base is a clamp, which is disposed on the outer periphery of the pier, and the clamp includes two semicircular rings, wherein the connecting rod is disposed on the top of one of the semicircular rings.

[0017] In a possible implementation, the fixed base includes a foundation pile buried in the ground, a force transmission frame and a support block. The foundation pile is buried in the ground, and the top protrudes from the ground. The top of the foundation pile is provided with a hinge hole along its own radial direction. The middle part of the force transmission frame is hinged to the hinge hole, and the hinge axis is parallel to the length direction of the reaction frame. The positioning rod is provided on the upper surface of one end of the force transmission frame, and the support block is provided at the bottom of the other end of the force transmission frame and abuts against the ground.

[0018] In a possible implementation, the connecting rod includes a plurality of segment rods connected sequentially from top to bottom, a transition sleeve is provided between two adjacent segment rods, two ends of the transition sleeve are respectively screwed to the two adjacent segment rods, and the rotation directions of the two segment rods are opposite.

[0019] Compared with the prior art, the bridge pre-back pressure device provided by the utility model has a fixed base arranged under the bridge bracket, the reaction frame is fixed by connecting rods and the fixed base, and the jacking drive is arranged between the bridge bracket and the reaction frame. When the jacking drive pushes the reaction frame upward, the reaction frame is fixed by the connecting rod, so that the jacking drive applies force in the opposite direction to push the bridge bracket downward, thereby detecting the pressure bearing capacity of the bridge bracket. Compared with the prior art, the reaction frame and the jacking drive used in the present application have no weight requirements, and the back pressure of the jacking drive is used to replace the gravity pressure of the existing heavy objects. The reaction frame and the jacking drive are small in size and weight, and have low transportation difficulty and low transportation risk. The reaction frame is fixed by the connecting rod, which is easy to disassemble, thereby greatly reducing the construction difficulty of the pre-back pressure process. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0021] Figure 1 A schematic diagram of the assembly of a bridge pre-reverse pressure device and a bridge bracket provided in the first embodiment of the utility model;

[0022] Figure 2 This is a schematic diagram of the structure of the bridge pre-reverse pressure device used in the first embodiment of the present utility model;

[0023] Figure 3 This is a schematic diagram of the structure of the connection assembly used in the second embodiment of the present utility model;

[0024] Figure 4 This is a schematic diagram of the assembly of the jacking assembly and the reaction frame used in the third embodiment of the present utility model;

[0025] Figure 5 This is a schematic diagram of the structure of the fixed base used in the fourth embodiment of the present utility model.

[0026] Description of reference numerals:

[0027] 1. Fixed base; 11. Positioning rod; 12. Foundation pile; 13. Force transmission frame; 14. Support block;

[0028] 2. reaction frame; 21. guide channel;

[0029] 3. Connecting assembly; 31. Connecting rod; 311. Section rod; 312. Transition sleeve; 32. Limiting plate; 33. Upper fastener; 34. Connecting sleeve;

[0030] 4. Lifting assembly; 41. Lifting drive member; 42. Fixed seat; 43. Guide rod;

[0031] 5. Bridge bracket. DETAILED DESCRIPTION

[0032] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0033] It should be noted that the terms "length", "width", "height", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "head", "tail", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the utility model.

[0034] It should also be noted that, unless otherwise clearly specified and limited, the terms such as "install", "connect", "connect", "fix", "set" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0035] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In addition, the meaning of "multiple" and "several" is two or more, unless otherwise clearly and specifically defined.

[0036] Please also read Figures 1 to 5, the bridge pre-back pressure device provided by the utility model is now described. The bridge pre-back pressure device includes a fixed base 1, a reaction frame 2, a connecting assembly 3 and a jacking assembly 4. The fixed base 1 is arranged below the bridge bracket 5 and is fixed relatively to the ground; the reaction frame 2 is arranged above the bridge bracket 5; the connecting assembly 3 includes a vertically arranged connecting rod 31, the upper end of the connecting rod 31 is connected to the reaction frame 2, and the lower end of the connecting rod 31 is connected to the fixed base 1; the jacking assembly 4 has a jacking drive member 41, the top end of the jacking drive member 41 is connected to the reaction frame 2, and the bottom end is abutted against the top of the bridge bracket 5.

[0037] It should be noted that Figure 1 The solid arrows in the figure represent the width direction of the bridge bracket, and the dotted arrows represent the length direction of the bridge bracket. Figure 2 The solid arrow in represents the length direction of the reaction frame 2.

[0038] It should be noted that the reaction frame 2 is a reaction plate, the reaction frame 2 is arranged in the horizontal direction, and the long axis of the reaction frame 2 is perpendicular to the length direction of the longitudinal and transverse beams.

[0039] During specific implementation, the reaction frame 2 may also be made of I-beam.

[0040] It should be noted that the bridge bracket 5 includes a bridge pier and horizontally arranged longitudinal and transverse beams, and the bottom end of the Dingsheng driving member 41 abuts against the longitudinal and transverse beams. The longitudinal and transverse beams have mesh holes, and the top of the connecting rod 31 passes through the mesh holes and is connected to the reaction frame 2.

[0041] Optionally, the lifting drive member 41 is a hydraulic cylinder, the piston rod of which moves in the up and down direction, and the top of the piston rod forms a lifting end. Of course, the lifting drive member 41 can also be other power structures, such as a cylinder. As long as it has a lifting end that can be extended up and down, it will not be listed here one by one.

[0042] During specific implementation, a plurality of bridge pre-back pressure devices may be provided, and the plurality of bridge pre-back pressure devices may be arranged at intervals along the length direction of the longitudinal and transverse beams.

[0043] Compared with the prior art, the bridge pre-back pressure device provided in the present embodiment has a fixed base 1 arranged under the bridge bracket 5, the reaction frame 2 is fixed by a connecting rod 31 and the fixed base 1, and a jacking drive 41 is arranged between the bridge bracket 5 and the reaction frame 2. When the jacking drive 41 pushes the reaction frame 2 upward, the reaction frame 2 is fixed by the connecting rod 31, so that the jacking drive 41 applies reverse force to push the bridge bracket 5 to move downward, and the pressure bearing capacity of the bridge bracket 5 can be detected; compared with the prior art, the reaction frame 2 and the jacking drive 41 used in the present application have no weight requirements, and the back pressure of the jacking drive 41 is used to replace the gravity pressure of the existing heavy objects. The reaction frame 2 and the jacking drive 41 are small in size and weight, and have low transportation difficulty and low transportation risk. The reaction frame 2 is fixed by the connecting rod 31, which is easy to disassemble, greatly reducing the construction difficulty of the pre-back pressure process.

[0044] In some embodiments, see Figure 1 and Figure 2 The connection assembly 3 further includes a limit plate 32, which is arranged above the reaction frame 2 along the width direction of the reaction frame 2, and the bottom end of the limit plate 32 abuts against the upper surface of the reaction frame 2. Two connecting rods 31 are provided, and the two connecting rods 31 are respectively connected to the two ends of the reaction frame 2. The two connecting rods 31 can fix the reaction frame 2 from both sides of the reaction frame 2, and can increase the horizontal stability of the reaction frame 2. After the reaction frame 2 is pushed by the jacking drive member 41, the fixing effect of the connecting rods 31 on both sides exerts a reaction force on the jacking drive member 41 vertically downward.

[0045] In some embodiments, see Figure 1 , the long axis of the reaction frame 2 is perpendicular to the length direction of the bridge bracket 5; there are multiple connection components 3, and the multiple connection components 3 are arranged at intervals along the long axis of the reaction frame 2; the two connection rods 31 in the same connection component 3 are respectively located on opposite sides of the reaction frame 2, and the long axis of the limit plate 32 is perpendicular to the long axis of the reaction frame 2. Multiple connection components 3 are arranged along the long axis of the reaction frame 2, so that the reaction frame 2 can evenly apply reaction force to the bridge bracket 5, the bridge bracket 5 is evenly stressed, and the bridge bracket is ensured to settle evenly, thereby ensuring the reliability of the measurement results.

[0046] In some embodiments, see Figure 1 and Figure 2 The lifting assembly 4 also includes a fixing seat 42, the bottom end of the lifting drive 41 is connected to the fixing seat 42, and the fixing seat 42 abuts against the upper surface of the bridge bracket 5. The fixing seat 42 has a large contact area with the bridge bracket 5, which can increase the force-bearing area of ​​the bridge bracket 5, avoid excessive local force, and cause uneven settlement of the bridge bracket 5, resulting in inaccurate detection results. The plate surface of the fixing seat 42 is uniform, which can facilitate the installation of the lifting drive 41 and reduce the difficulty of installation.

[0047] During specific implementation, the fixing seat 42 is an I-beam, and both ends of the I-beam are connected to the bridge bracket 5 .

[0048] In some embodiments, see Figure 4 The fixing seat 42 is provided with a guide rod 43 extending upward, and the reaction frame 2 is provided with a guide channel 21 corresponding to the guide rod 43, and the guide rod 43 is slidably matched with the guide channel 21. The setting of the guide rod 43 can further ensure the reaction direction of the reaction frame 2, ensure that the jacking drive member 41 applies pressure in the vertical downward direction, and improve the accuracy of the test results. The guide rod 43 can guide the movement of the lifting end to ensure that the lifting end always moves in the vertical direction.

[0049] In some embodiments, see Figure 1 and Figure 2 The connection assembly 3 also includes an upper fastener 33. The limit plate 32 is provided with a connecting hole corresponding to the connecting rod 31, and the top of the connecting rod 31 passes through the connecting hole and is connected to the upper fastener 33. The upper fastener 33 is screwed to the top of the limit plate 32 to limit the limit plate 32 from rising. The upper fastener 33, as a limiter, can prevent the limit plate 32 from rising, so that the limit plate 32 blocks the reaction frame 2 from moving upward, ensuring that the reaction frame 2 applies a reaction force downward, thereby ensuring the normal operation of the pre-reverse pressure operation.

[0050] In specific implementation, the upper fastener 33 is a nut, and the upper end of the connecting rod 31 is provided with a thread. The connecting rod 31 and the nut thread cooperate, and the nut blocks the limit plate 32 from above, so that the limit plate 32 can prevent the reaction frame 2 from rising.

[0051] In a specific implementation, the upper fastener 33 may also be a buckle, which is locked on the outer periphery of the connecting rod 31. The buckle will not move along the axial direction of the connecting rod 31 to ensure that the limiting plate 32 will not move upward.

[0052] In some embodiments, see Figure 3 , a positioning rod 11 is provided at the top of the fixed base 1, and the positioning rod 11 is a screw rod. The bottom of the connecting rod 31 is provided with an external thread, and the rotation directions of the positioning rod 11 and the connecting rod 31 are opposite; the connecting assembly 3 also includes a connecting sleeve 34, and the two ends of the connecting sleeve 34 are respectively screwed to the positioning rod 11 and the connecting rod 31. The positioning rod 11 reduces the difficulty of connecting the connecting rod 31 and the fixed base 1. The positioning rod 11 is stably connected to the connecting rod 31 through the connecting sleeve 34, realizing a detachable connection, facilitating the disassembly and replacement of the connecting rod 31, and reducing the difficulty of installation. The connecting sleeve 34 can slightly adjust the top height of the connecting rod 31, which is convenient for the staff to make fine adjustments.

[0053] In specific implementation, the fixed base 1 is cast concrete. When the concrete is cast, the positioning rod 11 is inserted at a specified position. After the fixed base 1 is formed, the positioning rod 11 and the fixed base 1 are formed as one piece, thereby improving the connection stability.

[0054] In some embodiments, the fixed base 1 is a clamp, which is arranged on the periphery of the pier, and includes two semicircular rings, and a positioning rod 11 is arranged on the top of one of the semicircular rings. The clamp can be fixed on the pier to maintain its own stability, thereby ensuring that when the reaction frame 2 is subjected to force, the clamp can keep the reaction frame 2 stable through the connecting rod 31, thereby ensuring the normal operation of the pre-reverse pressure.

[0055] In specific implementation, the two ends of the two semicircular rings are connected to each other, and the two connection points are located on the same vertical plane, and the long axis of the reaction frame 2 is parallel to the vertical plane. A positioning rod 11 is provided on the top of the semicircular ring away from the bridge pier.

[0056] When the vertical plane where the two connection points are located is perpendicular to the long axis of the reaction frame 22, a positioning rod 11 is provided on the top of the two semicircular rings at one end away from the bridge pier.

[0057] In some embodiments, see Figure 5 The fixed base 1 includes a foundation pile 12 buried in the ground, a force transmission frame 13 and a support block 14. The foundation pile 12 is buried in the ground, and the top protrudes from the ground. A hinge hole is opened at the top of the foundation pile 12 along its own radial direction. The middle part of the force transmission frame 13 is hinged to the hinge hole, and the hinge axis is parallel to the length direction of the reaction frame 2; a positioning rod 11 is provided on the upper surface of one end of the force transmission frame 13, and the support block 14 is arranged at the bottom of the other end of the force transmission frame 13 and abuts against the ground.

[0058] In a specific implementation, the support block 14 can be a metal block of a steel structure, or a hydraulic cylinder that can be extended and retracted in the up and down directions.

[0059] During specific implementation, the top end of the support block 14 abuts against the bottom surface of the force transmission frame 13 , and the bottom end abuts against the bottom surface.

[0060] In specific implementation, the support block 14 can be welded to the bottom of the force transmission frame 13, or fixedly connected by bolts, or directly abutted, as long as the support block 14, the force transmission frame 13 and the ground are relatively fixed during use to prevent the connecting rod 31 from moving up and down.

[0061] The foundation pile 12 is buried in the ground and has a strong gripping ability, so that when the jacking drive 41 pushes the reaction frame 2 to move upward, the foundation pile 12 is driven upward by the reaction frame 2 through the connecting rod 31. The support block 14 is arranged at the other end of the reaction frame 2. When the end of the reaction frame 2 connected to the connecting rod 31 is driven to move upward, the support block 14 limits the rotation of the force transmission frame 13, so that the force transmission frame 13 remains stable and still, thereby limiting the movement of the connecting rod 31, and ensuring that the reaction frame 2 causes the jacking drive 41 to apply a downward reaction force. The foundation pile 12 occupies a small area, saves space, and is easy to handle. Compared with the cast concrete fixed base, it shortens the preparation efficiency, reduces the use space, and saves the manufacturing cost. After the pressure is completed, the pile foundation can be taken out and recycled, and used in the next bridge construction, which improves the utilization rate.

[0062] In some embodiments, see Figure 3 The connecting rod 31 includes a plurality of segment rods 311 connected sequentially from top to bottom, and a transition sleeve 312 is provided between two adjacent segment rods 311. The two ends of the transition sleeve 312 are respectively screwed to the two adjacent segment rods 311, and the two segment rods 311 have opposite rotation directions. The arrangement of the plurality of segment rods 311 makes the length of the connecting rod 31 controllable. During on-site construction, steel bars of different lengths or diameters can be used for assembly, which saves costs and improves the utilization rate of on-site resources.

[0063] In a specific implementation, the diameters of each segment rod 311 may be the same or different, and corresponding screw grooves are respectively provided at both ends of the transition sleeve 312 , and the screw grooves are screwed to the corresponding segment rod 311 .

[0064] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A bridge pre-back pressure device, characterized in that: include: The fixed base is arranged below the bridge bracket and is fixed relatively to the ground; The reaction frame is located above the bridge bracket; A connecting assembly, comprising a connecting rod arranged vertically, wherein the upper end of the connecting rod is connected to the reaction frame, and the lower end of the connecting rod is connected to the fixed base; as well as The jacking assembly comprises a jacking driving member, the top end of which is connected to the reaction frame, and the bottom end of which is abutted against the top of the bridge bracket.

2. The bridge pre-back pressure device according to claim 1, characterized in that: The connecting assembly also includes a limit plate, which is arranged above the reaction frame along the width direction of the reaction frame, and the bottom end of the limit plate abuts against the upper surface of the reaction frame. Two connecting rods are provided, and the two connecting rods are respectively connected to the two ends of the limit plate.

3. The bridge pre-back pressure device according to claim 2, characterized in that: The long axis of the reaction frame is perpendicular to the length direction of the bridge bracket; there are multiple connecting components, and the multiple connecting components are arranged at intervals along the long axis of the reaction frame; the two connecting rods in the same connecting component are respectively located on opposite sides of the reaction frame, and the long axis of the limit plate is perpendicular to the long axis of the reaction frame.

4. The bridge pre-reverse pressure device according to claim 1, characterized in that: The jacking assembly also includes a fixed seat, the bottom end of the jacking drive is connected to the fixed seat, and the fixed seat abuts against the upper surface of the bridge bracket.

5. The bridge pre-reverse pressure device according to claim 4, characterized in that: The fixing seat is provided with a guide rod extending upward, the reaction frame is provided with a guide channel corresponding to the guide rod, and the guide rod is slidably matched with the guide channel.

6. The bridge pre-reverse pressure device according to claim 2, characterized in that: The connecting assembly also includes an upper fastener. The limit plate is provided with a connecting hole that passes through the upper and lower parts corresponding to the connecting rod. The top end of the connecting rod passes through the connecting hole and is screwed to the upper fastener. The upper fastener abuts against the top end of the limit plate to limit the rise of the limit plate.

7. The bridge pre-reverse pressure device according to claim 1, characterized in that: A positioning rod is provided on the top of the fixed base, and the positioning rod is a screw rod. An external thread is provided on the bottom of the connecting rod, and the rotation directions of the positioning rod and the connecting rod are opposite. The connecting assembly also includes a connecting sleeve, and the two ends of the connecting sleeve are respectively screwed to the positioning rod and the connecting rod.

8. The bridge pre-reverse pressure device according to claim 7, characterized in that: The fixed base is a clamp, which is arranged on the outer periphery of the pier. The clamp includes two semicircular rings, and the connecting rod is arranged on the top of one of the semicircular rings.

9. The bridge pre-reverse pressure device according to claim 7, characterized in that: The fixed base includes a foundation pile buried in the ground, a force transmission frame and a support block. The foundation pile is buried in the ground, and the top of the foundation pile protrudes from the ground. A hinge hole is opened at the top of the foundation pile along its own radial direction. The middle part of the force transmission frame is hinged to the hinge hole, and the hinge axis is parallel to the length direction of the reaction frame. The positioning rod is provided on the upper surface of one end of the force transmission frame, and the support block is arranged at the bottom of the other end of the force transmission frame and abuts against the ground.

10. The bridge pre-reverse pressure device according to claim 1, characterized in that: The connecting rod comprises a plurality of segment rods connected in sequence from top to bottom, a transition sleeve is arranged between two adjacent segment rods, two ends of the transition sleeve are respectively screwed to the two adjacent segment rods, and the rotation directions of the two segment rods are opposite.

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